Selecting portion of a JPanel

I need some help understanding how I would need to structure my classes to obtain the following behavior.

I need to provide the ability for a user to select a portion of a JPanel such that the user should be able to see a box around the selecion area as he drags his mouse to select a portion of the JPanel. My final aim is to obtain the Rectangle coordinates for the selection, so that I can create an image out of the selected portion.

Now, from my little understanding, I think it would be necessary to subclass JPanel so that I can override paintComponent(Graphics) in order for the box to be displayed while dragging. Is this true? Ideally, wouldn't it be better if I could have a class A in which I create a JFrame, add a JPanel to it, and then do something like B b = new B(panel);

Now, the B class would really be the selection utility class, in which I do all the required initialization, look for mouse events and mouse motion events, and draw the box around the selected area of the panel.

Am I making sense? If you could please provide some basic code outline/structure on how to arrange my classes, that's be very helpful.

Thanks.

I have the same problem and i also need the solution of it desperately as i have to implement it in my java program.
I believe it must be possible as there are classes to do every piece of work in java. I just don't know how to do it.
Anyone out there please help.

mousePressed gives you your starting point

mouseDragged gives you the rectangle from the starting point to the drag point,
changing the rectangle co-ords as it goes, and calling panel.repaint() for the panel's
paintComponent() to draw the dashed horizontal/vertical lines (BasicStroke)